IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Hemisynthesis, NMR Characterization and UHPLC-Q-Orbitrap /MS² identification of (+)-Catechin oxidation products in red wines and grape seed extracts

Hemisynthesis, NMR Characterization and UHPLC-Q-Orbitrap /MS² identification of (+)-Catechin oxidation products in red wines and grape seed extracts

Abstract

(+)-Catechin—laccase oxidation dimeric standards were hemi-synthesized using laccase from Trametes versicolor in a water-ethanol solution at pH 3.6. Eight fractions corresponding to eight potential oxidation dimeric products were detected. The fractions profiles were compared with profiles obtained with two other oxidoreductases: polyphenoloxidase extracted from grapes and laccase from Botrytis cinerea. The profiles were very similar, although some minor differences suggested possible dissimilarities in the reactivity of these enzymes. Five fractions were then isolated and analyzed by 1D and 2D NMR spectroscopy. The addition of traces of cadmium nitrate in the samples solubilized in acetone-d6 led to fully resolved NMR signals of phenolic protons, allowing the unambiguous structural determination of six reaction products, one of the fractions containing two enantiomers. These products were then analyzed in grape seed extracts and red wines (UHPLC-Q-Orbitrap MS). The different dimers had different fragmentation patterns according to their interflavan linkage position. Oxidation dimeric compounds had a specific fragment ion at m/z 393, missing for B-Type dimers fragmentations. A fragment ion at m/z 291 occurred and was specific for oxidation dimeric compounds with a C-O-C linkage. Higher level oxidation products had abundant specific fragments: m/z 425, 397 and 245. These fragmentations were useful to identify them in complex samples such as grape seed extracts and wines. Three grape varieties and three ripening stages were selected and the corresponding seed extracts were obtained. The analyses revealed an increasing trend for the oxidation markers during grape ripening. The analysis of Syrah wines (2018, 2014, 2010) showed a decreasing trend of these molecules during wine ageing which might be due to further oxidation.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Saucier Cedric1, Deshaies Stacy1, Le Guernevé Christine1,2, Sommerer Nicolas1,2, Garcia Lucas Suc François1, Mouls Laetitia1

1SPO, Université de Montpellier, INRAE, Institut Agro, UMR SPO, Faculté de Pharmacie, 15 avenue Charles Flahault, 34000 Montpellier, France
2INRAE, PROBE Research Infrastructure, PFP Polyphenol Facility, 34060 Montpellier, France

Contact the author

Keywords

wine, grape, polyphenol,oxidation, catechin

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Monitoring vineyard canopy structure by aerial and ground-based RGB and multispectral imagery analysis

Unmanned Aerial Vehicles (UAVs) are increasingly used to monitor canopy structure and vineyard performance. Compared with traditional remote sensing platforms (e.g. aircraft and satellite), UAVs offer a higher operational flexibility and can acquire ultra-high resolution images in formats such as true color red, green and blue (RGB) and multispectral. Using photogrammetry, 3D vineyard models and normalized difference vegetation index (NDVI) maps can be created from UAV images and used to study the structure and health of grapevine canopies. However, there is a lack of comparison between UAV-based images and ground-based measurements, such as leaf area index (LAI) and canopy porosity.

Construction of a 3D vineyard model using very high resolution airborne images

In recent years there has been a growth in interest and number of research studies regarding the application of remote optical and thermal sensing by unmanned aerial vehicle (UAV) in agriculture and viticulture. Many papers report on the use of images to map or estimate the growth and water status of plants, or the heterogeneity of different parcels. Most often, NDVI or other similar indices are used.

“Compost Application in the Vineyard: Effects on Soil Nutrition and Compaction”

The mechanization of pruning and harvesting in vineyards has increased the risk of soil compaction. To reclaim soil properties or avoid this degradation process, it is crucial to properly manage the soil organic matter, and the application of compost derived from the vines themselves is a strategy to achieve this. The objective of this study was to evaluate the properties of soil treated with different doses of compost applied both on the vine row and the inter rows of a Vitis vinifera crop.

How to resolve the lack acidity in wines by better understanding of the adequation of grape varietal-terroir: Negrette grape in the terroir of Côtes du Frontonnais

Le manque d’acidité des vins est un sujet préoccupant dans de nombreux vignobles car l’acidité est un facteur déterminant de la qualité des vins, en liaison avec la nutrition minérale de la vigne.

Better understand the soil wet bulb formation with subsurface or aerial drip irrigation in viticulture

The gradual change in rainfall patterns experienced in the south of France vineyards, especially around the Mediterranean sea, means that the vines are increasingly subject to summer drought. The winegrowers developped the use of irrigation techniques to ensure the maintenance of competitive yields in the production of wines under Protected Geographical Indication label. In practice, drip irrigation pipes can be installed above the ground or buried into the soil as well as at different distances from the vine row. The objective of this study was to examine the profiles of the wet bulbs of the soil obtained from two drip irrigation systems : aerial drip located under the vine row and subsurface drip placed in the middle of the inter-row. This experiment took place over two consecutive seasons (2020-2021) on a 3.4 ha Viognier plot in the Mediterranean region (PGI Oc, France) on sandy clay soil. The annual rainfalls were less than 400 mm. Soil water content probes were installed at different depths (20 – 40 – 60 – 80 cm) and at different lateralities from the vine row (30 – 60 – 90 – 120 cm) to control the formation of the soil wet bulb during irrigation. The mapping and the analysis of the data allowed a better understanding and differentiation of the water percolation when irrigating with subsurface or aerial drip. For the same amount of water and without differences of vine water status, it is shown that in a subsurface drip irrigation situation, the size of the wet bulb formed is larger than in aerial drip irrigation system.